Sea Trout Fishing Information

What is a Sea Trout

Over the years much information about sea trout has been misleading. Firstly, for the information of our cousins in the USA, a Sea Trout is not what you call a Sea Trout in the USA. When we say Sea Trout we mean Sea-Run Brown Trout, quite a difference!.
It was only a year or two back that I received a most strident email from a professional ghillie stating that I was wrong in mentioning that the Brown Trout and the Sea Trout were the same species, his email making it clear the Sea Trout was a totally different species. Needless to say he was wrong, but it only goes to illustrate the confusion in some minds.

The Sea Trout is termed an anadromous fish; a fish which breeds and spends its early life in freshwater, before migrating to the sea.. It then returns as an adult to freshwater to breed and continue the species. So to put it simply, the Sea Trout is a Brown Trout (Salmo trutta) that heads out to the sea. There are many theories regarding this migration, the most probable one being, the lack of food within the river system makes such migration necessary for survival. Evolution has taught the Sea Trout that the abundance of food in the sea gives them an evolutionary advantage.

One effect of migration to the sea is that sea trout can grow big, very big and fish in excess of 10lbs are not unusual and much larger fish are caught throughout the UK each year. The abundance of food in the sea makes this possible. Many rivers that have serious runs of sea trout are notable for the small size of their resident Brown Trout.

Like the Salmon, Sea Trout must return to freshwater to breed. Both fish await the right conditions to head upstream from the sea. Floods and high water bring the Sea Trout up the rivers in shoals. In many of the rivers we fish, the larger fish often enter the river earlier in the year and the smaller fish later, although this cannot be taken as the case in all rivers.

Life Cycle of the Sea Trout

The life cycle of the Sea Trout starts as an egg laid in gravel (known as redds) and runs as follows:-

EGG - Laid in gravel, the female Sea Trout uses her tail to dig out a depression in the gravel, before depositing her eggs to be fertilized by the cock fish. She then uses her tail to to cover the eggs with the removed gravel. The gravel beds used in this way are known as Redds

ALEVIN - When the egg hatches the fish emerges with a yolk sac attached. This yolk sac provides the initial food source for the newly hatched fish. When the yolk sac is used up the small fish is then known as a Fry. During the alevin stage the fish stays very much within the redd for protection.

FRY - The small fry begins to move away from the redd and find their own territory feeding on whatever is available, minute invertebrates etc. As the fry grows it begins to develop the markings known as Parr Markings and from this time it is known as a Parr.

PARR - The fish at this stage is upto 15cm in length (although this depends on many conditions). The larger size means they can eat larger food this can lead to faster growth. When the time and conditions dictate, the Parr develops a bright silver coating over its scales. It is at this point that the fish becomes known as a smolt and is the indicator that it is about to head downstream to the sea.

SMOLT - The fish is now bright silver in appearance and it undergoes other physiological changes which allow survival in salt water. On entry to the sea the Smolt is now a young Sea Trout.

YOUNG SEA TROUT - Peel, Herling, Finnock, Whitling are just 4 regional names used for young sea trout that return in large shoals to the rivers to spawn. Those fish that return after one year or more can truly be known as Sea Trout and are generally at least 10 times the weight of a trout hatched at the same time that remained in the river.

SEA TROUT - The adult fish returning to freshwater and one of the great prizes. Those fish that have recently returned are known as "Fresh Run". When in freshwater the Sea Trout undergoes many changes. The bright silver colour begins to become dull and the fish start to "colour" ready for spawning. In addition the males jaw grows larger and they develop a prominant hook on the lower jaw, known as a kype.

KELT - After spawning the surviving fish are known as kelts. These head back to the sea quickly and the whole cycle begins again

Where to find Sea Trout

Sea trout may be one of the most enigmatic of game fish, but that doesn't mean they are difficult to find. At one time most, if not all, rivers that held brown trout and had access to the sea had a population of sea trout. Man has not been helpful and pollution, overfishing, the blocking of rivers preventing access to suitable breeding water and the modern curse of the fish farms, have all contibuted to the decline of the sea trout. Saying that good fishing can be found throughout the England, Scotland and Wales.

Some Suggested Rivers

The following list is far from complete and I apologise if your favourite river is not on it. That said they are all excellent sea trout rivers.